It seems to be used to describe every brand/product that I read about (work in a creative field so see this stuff a LOT) and it drives me bonkers. It's the equivalent of people who say they're 'a little bit crazy' - no you're not, you're just like anyone else. Likewise 'quirky' decor/dress sense/whatever - it's not, it's like 90% of what else is out there. A less over-used description of your product would be much more 'quirky' than this cliched rubbish.